Pre-redevelopment audits and reuse targets

Most pre-redevelopment audits arrive too late to change anything. The demolition package has been priced, the programme assumes a grab lorry and a skip, and the audit becomes a record of what was thrown away rather than a tool for deciding what to keep. That timing problem, not the survey method, is what makes the difference between a real reuse target and a paragraph in a planning document.

An audit done at the right moment tells you what is in the building, what it is worth, and what has to change in the design and the contract for any of it to be reused. Done at the wrong moment it tells you the tonnage.

What the audit records

A Pre-redevelopment Audit is a structured inventory of the existing building and site before demolition or strip out. The core of it is a schedule of elements with quantities, materials, condition and a reuse route for each.

The elements worth recording in detail are the ones with value or with a disposal cost: structural steel and its connections, precast and in situ concrete, brick and stone, timber, raised access floors, suspended ceiling systems, doors and ironmongery, sanitaryware, mechanical plant, electrical distribution gear, lifts, glazing and cladding, and external hard landscaping.

For each element the audit should give quantity by mass and by area or number, a condition grade, and a route. The hierarchy of routes is retain in situ, reuse on site, reuse off site, recycle, recover, dispose. Retention in situ is the one that gets skipped, and it is the one with the largest carbon saving.

Photographs matter. So does a drawing marked up with where each element sits, because a schedule without locations is unusable on site.

Timing it so the findings can be acted on

Run the audit while the design is still moving, which in practice means before the demolition scope is written and before the structural strategy is fixed.

The sequence that works:

1. Desk review of existing drawings, asbestos records and previous surveys.
2. An access visit early enough that the findings can change the design, not merely describe it.
3. A first schedule with indicative quantities, issued to the design team and the cost consultant together.
4. Design decisions taken against that schedule: which elements are retained, which are reused in the new build, which go to market.
5. The final audit, with quantities firmed up, issued as a contract document.

The two access problems are a tenanted building and a live operation. Both are solvable with an intrusive survey allowance and some patience, and neither is a reason to defer the audit to the contractor. A contractor commissioned to demolish a building has no commercial reason to find reasons not to.

Where the building is being surveyed for asbestos anyway, under the Control of Asbestos Regulations 2012, that visit is the natural point to gather the audit information as well. Two surveys, one scaffold hire.

Setting targets that survive procurement

A reuse target written into a planning document and nowhere else does not survive the first value engineering exercise. The target has to appear in three places: the planning submission, the employer's requirements, and the demolition and enabling works scope.

Useful targets are expressed as a proportion of the audited quantity rather than as an abstract percentage. "Reuse on site of the audited raised access floor, at least 80 per cent by area" can be checked. "Maximise reuse where practicable" cannot. Where the authority sets its own benchmarks, as the London Plan circular economy policy does through the Mayor's guidance, use those figures and cite the current version of the guidance rather than an older note, because they are revised.

Put a reporting obligation in the same clause as the target. A commitment with no measurement date is a commitment nobody will be asked about.

Reporting against the targets after completion

The post-completion report closes the loop, and it is usually secured by planning condition where the authority has taken the commitments seriously.

It needs the audited baseline, the actual quantities of each route with waste transfer documentation behind them, an explanation of any element that changed route and why, and the final figures against each target. Waste transfer notes and consignment notes are the evidence; a contractor's summary spreadsheet on its own is not.

Where a target was missed, say so and give the reason. Authorities are far more tolerant of a missed target with an explanation than of a report that quietly restates the target as achieved.

Where the audit overlaps with the waste documents

There is genuine overlap here, and the fix is to decide which document owns which content before any of them are drafted.

The audit owns the inventory of what exists. A Circular Economy Statement owns the strategy, the targets and the design response, drawing its numbers from the audit. A Site Waste Management Plan owns the construction phase arisings, the segregation arrangements and the carrier chain. A Waste Management Strategy owns the operational waste of the completed building, which is a different subject entirely and is frequently confused with the others.

Our note on how a circular economy statement is structured sets out that document in more detail.

The carbon argument sits in a Whole Life Carbon Assessment, which takes the retention and reuse decisions from the audit and prices them in kgCO2e. Retention in situ usually dominates that assessment, which is why the audit should be finished before the whole life carbon work starts rather than alongside it.

Storage, logistics and the reasons reuse fails on site

Reclaimed material needs somewhere to go between removal and reinstallation, and on a tight urban site that space does not exist. This is the most common practical reason a reuse target quietly fails.

Plan for it: a defined laydown area with a weatherproof cover, a double handling allowance in the programme, and a decision on whether material leaves site and comes back or stays. Off site storage costs money for months and the cost lands on the demolition contractor unless somebody else takes it.

Structural reuse brings its own requirements. Reused steel needs traceability, testing and a structural engineer prepared to specify it, and the insurance and warranty position has to be settled before the design relies on it. Non-structural elements are far easier, which is why raised floors, doors, ironmongery and sanitaryware account for most successful reuse in practice.

Securing it by condition

Ask for the wording rather than waiting for it. A condition requiring the audit to be submitted before demolition begins is common. A condition requiring the post-completion report within a defined period of practical completion is better, because it is the one that gives the target teeth.

Watch for conditions that require approval of an audit before any works at all, including enabling works and site investigation. That drafting stops the intrusive survey you need to complete the audit, and it is worth negotiating at the drafting stage rather than discovering on site.

PlanScope drafts pre-redevelopment audit and circular economy documents from your project details, marking site specific facts it cannot verify rather than filling them in, and the survey work itself still needs a competent surveyor. For specialist technical reports, qualified professional input may be required.

This is general guidance, not legal advice; check the position with your local planning authority or a qualified professional before relying on it.

PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.